The Canadian government has amassed both human and signals intelligence in a months-long investigation of a Sikh activist’s murder, which it has alleged was done by India, CBC News reported on Friday.

The unprecedented tensions flared up on Monday after Canadian Prime Minister Justin Trudeau said Ottawa was “actively pursuing credible allegations” linking Indian government agents to the murder of Hardeep Singh Nijjar, 45, outside a Sikh temple in British Columbia in June.

The two countries, whose relations have been fraying in recent years over the issue of Sikh separatists, have since announced tit-for-tat expulsions of senior diplomats and issued tit-for-tat travel advisories.

Indian PM Narendra Modi’s government denied any links to the alleged murder. While calling on India to cooperate with the investigation into the murder, Canada said on Thursday it would not release its evidence.

Traditional Canadian allies have so far taken a relatively cautious approach to the matter. Analysts say this is partly because the United States and other major players see India as a counterweight to the growing influence of China.

Today, quoting Canadian government sources, CBC News said the “intelligence includes communications involving Indian officials themselves, including Indian diplomats present in Canada”.

It added that the intelligence “did not come solely from Canada” and some was also provided by “an unnamed ally in the Five Eyes” alliance — an intelligence-sharing network that includes the US, the UK, Canada, Australia and New Zealand.

The Canadian publication went on to add that the slain Sikh leader “reportedly had been warned by the Canadian Security Intelligence Service that he was at risk”.

The report further said that “in a diplomatic crisis that unfolded progressively behind the scenes, Canadian officials went to India on several occasions seeking cooperation” in the investigation of Nijjar’s death.

CBC News said that Canada’s National Security and Intelligence Adviser Jody Thomas was in India over four days in mid-August. Another five-day visit this month overlapped with a “tense meeting” between the two countries’ premiers, it added.

The report quoted Canadian sources as saying: “When pressed behind closed doors, no Indian official has denied the bombshell allegation at the core of this case — that there is evidence to suggest Indian government involvement in the assassination of a Canadian citizen on Canadian soil.”

“I can assure you that the decision to share these allegations on the floor of the House of Commons … was not done lightly,” CBC quoted Trudeau as stating yesterday after attending the 78th UN General Assembly in New York. “It was done with the utmost seriousness.”

‘Not some special exemption’ for India, US says

Meanwhile, the US is in touch with Indians at high levels and Washington is giving India no “special exemption” in the matter, its national security adviser Jake Sullivan said on Thursday.

The United States has been seeking to strengthen its relationship with India. President Joe Biden hosted Modi for a state visit at the White House earlier this year.

Asked whether US concern over the incident could disrupt that process, Sullivan said the United States would stand up for its principles, regardless of what country is affected.

“It is a matter of concern for us. It is something we take seriously. It is something we will keep working on, and we will do that regardless of the country,” Sullivan told reporters at the White House.

“There’s not some special exemption you get for actions like this. Regardless of the country, we will stand up and defend our basic principles and we will also consult closely with allies like Canada as they pursue their law enforcement and diplomatic process.”

Sullivan noted that the United States was in touch with both countries about the topic. “We are in constant contact with our Canadian counterparts … and we have also been in touch with the Indian government,” Sullivan said.

Earlier, John Kirby, spokesman for the White House National Security Council (NSC) had said it supported Canada’s efforts to investigate the killing and encouraged India to cooperate in the probe.

Separately, another NSC spokesperson, Adrienne Watson, had denied reports that the US had “rebuffed” Canada over the matter.

Australia had expressed “deep concern” over Canada’s accusations while Britain said it was in close touch with its Canadian partners about the “serious allegations”.

Prime Minister Anwaarul Haq Kakar had a day ago termed the rising wave of Hindutva or Hindu nationalism a “matter of deep concern” for the international community.

The Foreign Office had also said the accusation showed that New Delhi’s “network of extra-territorial killings” had gone global while Foreign Secretary Syrus Qazi said Pakistan was not surprised by the Canadian accusation.